Nowadays, bumper beams for passenger cars are usually adapted to absorb impact energy by being deformed plastically. In small cars, the beam can be arranged to absorb enough energy. In bigger cars, energy absorbing elements need to be arranged between the side beams of the car and the bumper beam. DE-19537186-A shows such elements in the form of deep drawn rectangular boxes. U.S. Pat. No. 3,998,485-A shows circular, stepped tubes as extensions of the side beams of a car.